Can I heat up cooked food with its liquid on a blech on Shabbos?
Please note, some of the liquid may have congealed.
According to some Posqim, it is assur to heat up cold food that is liquid or congealed. This is the view of Rashi, Rosh and Smag.
According to other Posqim, it is mutar to heat up all types of food, solid or liquid, as long as the food in question was completely cooked before Shabbath.
This is the view of Rambam, Rashba and Ran. This is the opinion which I follow.